*3.3. Relaxation of Boundary Conditions*

To solve the stability model, we need to relax the boundary conditions as proposed by Harris et al. [64]. For that reason, the conditions *<sup>F</sup>*0(*η*) → 0 as *η* → ∞ can be replaced by new conditions *<sup>F</sup>*0(0) = 1. It must be pointed out that the linearized boundary value problem (25)–(28) together with new conditions *<sup>F</sup>*0(0) = 1 will yield the unlimited set of unknown eigenvalues (*<sup>γ</sup>*1 < *γ*2 < *γ*3 < ...). If the smallest eigenvalues *γ* show a positive sign, the solutions observed an initial decay of perturbation and accordingly indicates a stable solution. On the other hand, as the smallest eigenvalues *γ* show a negative sign, an early growth of disruption is noticed which consequently signifies unstable solution.
